In a measurement system of this type, the measured data needs to be extensively processed to extract the relevant part of the echo profile from interference. This can lead to unreliable and inaccurate level measurement as the vessel environment changes. It is known to process the received information according to a set of parameters related to vessel conditions, but at present such parameters are adjusted during a setup procedure, and are chosen to be a compromise aimed at reliable operation in the worst environment likely to be encountered.
It will be appreciated that in a typical installation there are environmental parameters which can readily be measured and therefore applied in real time as an actual parameter; one example of this is the temperature of the material of interest. However, there are other relevant parameters which are difficult or impossible to measure and apply to the signal processing algorithm in real time. Examples of the latter are turbulence, froth height and froth density.